This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. The objectives of the research are to investigate 1) the mechanisms whereby a group of novel DNA-binding proteins, termed alpha/beta-type small, acid-soluble proteins (SASP) protect DNA in dormant spores of Bacillus species against a variety of damaging agents, and 2) how these proteins are subsequently removed during spore outgrowth, ultimately leading to 3) chromosomal replication. The studies will involve biochemical and biophysical elucidation of the properties of the alpha/beta-type SASP and the complexes of these proteins with DNA, the characterization of the spore protease, termed Gpr, that initiates SASP degradation during spore outgrowth, as well as characterization of PolE and PolC (apo and complexes with DNA template:primers) novel bacterial polymerases responsible for chromosomal DNA replication. A major goal of the proposed research is the characterization (mechanistic and functional) of all of these components including elucidation of their three-dimensional structures by x-ray crystallography. Success in achieving this goal will lead to an understanding at the molecular level of the mechanisms of DNA protection in dormant spores, the mechanisms responsible for the loss of this DNA protection during spore germination and outgrowth, and later mechanism of its replication in vegetative cells.